proposed relaxation of epa drinking water standards …

PROPOSEDRELAXATION OFEPA DRINKING

WATERSTANDARDS

FORRADIOACTIVITY

PREPARED BY

DANIEL HIRSCHJENNA MARXOctober 2008

FOR MORE INFORMATION CONTACT:COMMITTEE TO BRIDGE THE GAP

[email protected](831) 336-8003

www.committeetobridgethegap.org

Proposed Relaxation of EPA Drinking Water Standards for Radioactivity

The U.S. Environmental Protection Agency has drafted extraordinary new radiological

standards for responding to radiological releases from a wide range of events. A copy of the

secret draft “Protective Action Guidance for Radiological Incidents,” dated August 2007 and

marked “Please Do Not Distribute” and “Do Note Cite or Quote,” was obtained and made public

by Doug Guarino of the trade publication Inside EPA, who has written about the concerns the

document has triggered within EPA and among state regulators.1 We understand EPA is

contemplating soon issuing the draft.2 Here we analyze one of the most controversial aspects of

the document, its proposal to allow the public to ingest drinking water with radioactive

concentrations orders of magnitude higher than EPA’s longstanding radiological drinking water

standards permit.

Background

In the early 1990s, EPA issued its “Manual of Protective Action Guides and Protective

Actions for Nuclear Incidents.”3 Protective Action Guides, or PAGs, are radiation levels that

when exceeded trigger protective actions. For example, if a nuclear incident would in

contamination of soil at levels above the PAGs, people may be evacuated so as to keep their

radiation dose below the specified amount.

The PAGs applied to a range of nuclear incidents “at a variety of facilities, including, but

not limited to, those that are part of the nuclear fuel cycle, defense and research facilities, and

facilities that produce or use radioisotopes, or from the transportation or use of radioactive

materials at locations not classified as ‘facilities.’” The original PAG guidance and the current

proposed revision thereto divide the responses to a nuclear incident into: the early phase, the

intermediate phase, and long-term cleanup activities. The early phase last hours to days, the

intermediate phase months to years, and the long-term cleanup phase potentially many years.

The new draft PAGs EPA is reported to be contemplating soon releasing revise the

existing PAGs in numerous ways that have triggered great controversy. Despite the fact that

radiation is now officially deemed to be more dangerous than previously thought, virtually all of

the changes to the PAGs have been in the direction of permitting higher exposures to the public.4

1 The EPA document is available at http://www.committeetobridgethegap.org/pdf/pag102108.pdf

2 Although no substantive revisions to the August 2007 draft have been reported, it is possible

that there may have been some. The analysis here is based on the August 2007 draft.3 Issued by the EPA Office of Radiation Programs, Revised 1991, second printing 1992. Posted

at http://www.epa.gov/radiation/docs/er/400-r-92-001.pdf We will here refer to the existing

PAGs as the 1992 PAGs.4 EPA and other agencies requested and funded the National Academy of Sciences to prepare

updated cancer risk estimates for ionizing radiation based on the most current research. The

report, Health Risks from Exposure to Low Levels of Ionizing Radiation, National Academy

Press, 2006, estimated cancer risk at 1.14 cancers per 1000 person-rem, considerably higher than

2

For example, permitted exposures for the majority of radionuclides in the early phase

have increased. For 33 radionuclides, the permissible concentrations to which the public may be

exposed without protective actions being taken in the early phase have been increased, while for

only 19 have they been tightened.5 Furthermore, those that have had their limits relaxed have

done so by an average of 76%, whereas the radionuclides that have more limiting concentrations

have been tightened by only 34%.

Long-term cleanup is now proposed to use a much opposed process called “optimization”

that would allow the choice of radiation “benchmarks” as immensely high as 10 rem per year,

the equivalent of about 50,000 chest X-rays over a 30 year period and an associated cancer risk

of 1 in 3, according to current risk estimates prepared for EPA and other agencies.6 EPA

historically has insisted on an “acceptable” risk range of one in a million to one in ten thousand,

so contemplating “benchmarks” with a risk as high as every third person so exposed getting a

cancer from the exposure would be a radical departure from its entire history and ethically very

difficult to defend.7

These are deeply troubling proposed relaxations of longstanding EPA radiation

protections, for the early and late phase responses to a radiological releases. Without

diminishing our concern about those phases, we here focus on the intermediate phase PAGs, and

particularly those related to drinking water.

The Intermediate Phase PAGs

Under EPA’s longstanding PAGs for the intermediate phase, total dose to the public

without protective action is limited to 2 rem for the first year and 0.5 rem (500 millirem) per year

for subsequent years. The 1992 PAGs provide guidance in determining when those limits would

be exceeded. Part of that guidance were Protective Action Guides for the Intermediate Phase for

Food and Water (chapter 3 of the 1992 PAGs). The food PAGs were prepared by the Food and

past estimates used by EPA and other agencies, including the figures used by EPA in creating the

1992 PAGs.5 See Table 2-5 of the new PAGs (pp. 2-22 to 2-26) which compares, radionuclide by

radionuclide, the revised early phase PAGs with the 1992 ones.6 For a discussion of the problems of “optimization” and the employment of “benchmarks” in

long-term cleanup decisions, and the cancer risks associated with the radiation levels

contemplated, see the correspondence by dozens of organizations and individuals criticizing

new PAGs issued by the Department of Homeland Security for responding to “dirty bomb”

attacks. http://www.committeetobridgethegap.org/pdf/2006Ltr102108.pdf and

http://www.committeetobridgethegap.org/pdf/sfundgroup102108.pdf The controversial DHS

guidance for dirty bombs is now being proposed by EPA to be expanded to cover a wide range of

non-terrorist events involving radiological releases.7 Note that when we speak of cancer risks from exposure to radiation, these risks are in addition

to one’s normal risk of getting cancer; i.e., these are excess cancers, ones that would not have

appeared had it not been for the radiation exposure.

3

Drug Administration and included by EPA in the 1992 guidance. They specified that no more

than 0.5 rem per year should come from the ingestion pathway and calculated radioactive

concentrations to meet that limit. Importantly, the existing food PAGs include drinking water.

Also importantly, they were not additive on top of the overall dose limits, but a component of

them.

EPA is now proposing to turn its past guidance on its head. It now proposes to permit

one to add the 500 millirem food PAG to the overall dose limit. And it now proposes – even

though the food PAG already contains a water ingestion component – to create an entirely new

Drinking Water PAG, which would be added onto the general intermediate PAG and the food

PAG. In other words, if the existing overall intermediate dose limit is 2 rem for the first year and

0.5 rem for subsequent years, the proposed PAG would be for the first year 2 + 0.5 + 0.5 rem, or

3 rem; and for subsequent years 0.5 + 0.5 + 0.5 rem, or 1.5 rem – a tripling of permissible dose.

EPA would not just be double- or triple-counting, it would be doing so twice. Since

drinking water is already included in the 0.5 rem food ingestion PAG, creating a separate water

PAG that can be added to the food PAG counts the water radiation twice. And then permitting

the already duplicative food and water PAGs to the existing overall PAG radiation limit only

compounds the injury to public health.

Astronomically High Levels of Radioactivity in Drinking Water Proposed

Most troubling, however, are the absolutely astronomical values for radionuclides put

forward in the new Drinking Water PAGs, levels that are hundreds, thousands, and even millions

of times higher than EPA’s current drinking water standards for radiation.

For decades EPA has set permissible concentrations of radionuclides in drinking water.

These limiting levels, called Maximum Concentration Levels (MCLs), are established via the

Safe Drinking Water Act. Under certain emergency situations, levels higher than MCLs can be

used in determining when to take an urgent response (e.g., providing replacement water supplies

such as bottled water or requiring treatment of the water). Those longstanding EPA emergency

limits are called Removal Action Levels (RALs).

In the new draft PAGs, EPA proposes taking no response to protect people from

radioactivity in drinking water until concentrations rise to levels that are so high as to be frankly

beyond comprehension. It is difficult to believe any responsible EPA official would sign off on

radioactivity concentrations in drinking water that high. Yet, buried deep in the new PAGs is a

table – Table 4.1 – that puts forward radioactivity levels for drinking water so immense as make

it difficult to imagine what those responsible for the table could possibly have been thinking. No

comparison to existing EPA drinking water standards is provided in the new PAG document, so

it is likely responsible decision-makers who are asked to sign off on these revisions would have

no inkling of the significance, of how much a departure this is from EPA’s historical practices of

protecting members of the public from excessive radioactivity in their drinking water.

4

We here have performed the missing analysis, comparing the new proposed drinking

water radioactivity levels with EPA’s current drinking water requirements, radionuclide by

radionuclide. We can only hope that responsible officials within EPA and the Administration

more generally will, upon seeing the extraordinary magnitude of the dramatic change from

longstanding protective requirements proposed, not wish to carry the ethical stain of having

approved exposing the American public to radioactivity levels in their drinking water that would

shock the conscience.

The New Radioactivity Drinking Water PAGs

The draft PAG document calls the new drinking water limits Derived Response Levels,

or DRLs. The DRLs simply are the level of radioactivity in drinking water that EPA would

allow people to be exposed to without EPA taking a protective action like providing alternative

clean drinking water supplies. Like the existing EPA drinking water standards of MCLs and

RALs discussed above, the DRLs are measured in units of pico-Curies of radioactivity per Liter

of water – pCi/L.

Without discussion as to when one should use one or the other, two sets of DRLs are set

forth in the new PAGs – Derived Response Levels with and without decay. The DRLs with

decay apparently presume that the levels detected in drinking water will promptly decay based

on the half-life of the radionuclide, and therefore permit higher concentrations –and in some

cases, very much higher concentrations – than in the case where they don’t presume decay.

The assumption that you can permit people to be exposed to very high concentrations of

radioactivity in their drinking water because it will subsequently decay to lower levels is

questionable and contrary to most EPA practice. There are other factors besides radioactive

decay that affect concentrations in water. One frequently sees concentrations increase, as more

radioactivity from the contamination source moves into the groundwater. Increasing

concentrations wouldn’t be possible if the only factor involved were radioactive decay.

Additionally, some radionuclides decay into other radionuclides (“daughter products”), so rather

than the level of daughter products declining by decay, they actually increase in concentration.

EPA practice has historically been to take action when concentrations exceed permissible limits

and then stop those actions if and when the concentrations decline below those limits, not allow

exceedances based on the hope that sometime thereafter they will through decay or other means

go back down.

So there are two sets of proposed drinking water limits in the PAGs –DRLs with and

without decay.8 We here compare both to the longstanding EPA drinking water standards for

radioactivity, the MCLs and the RALs. The MCL is EPA’s primary drinking water standard

under the Safe Drinking Water Limit. Under CERCLA, EPA has also established emergency

response levels, the Removal Action Levels. (These aren’t long-term cleanup standards, which

8 One finds the DRLs with an without Decay in the last two columns of Table 4-1 in the new

PAGs.

5

use the MCLs, but time-urgent response standards that determine when actions like providing

alternative water supplies are immediately needed.)

The RALs are based on the MCL or the concentration of radioactivity in drinking water

that would produce a 10-4

(one in ten thousand) cancer risk, whichever is greater. The EPA

method for deriving the 10-4

concentration is described in Table 6 of this report. Many EPA

Regions simply use the MCLs for their emergency response levels for radioactivity rather than

the RALs, and EPA has now, for chemicals, established new RALs which are the MCLs. So the

primary comparison of the new proposed drinking water levels, DRLs, should be with the MCLs,

but for completeness purposes, we have also compared them with the RALs.

The Magnitude of Increased Permissible Radiation Exposure Proposed

Table 1 of this report compares the new with the existing drinking water standards. For

example, the DRL without decay for strontium-90 is 6,650 pCi/L without decay and 6730 with

decay (not much different because of its long life), whereas the current EPA MCL is 8 and the

RAL is 39. Thus EPA now proposes to permit people to be exposed at levels roughly a thousand

times higher than its current Safe Drinking Water Act limit (the MCL), and 170 times higher

than its emergency response level, the RAL. Iodine-131 has a DRL without decay of 8490 an

with decay of 267,000; the MCL is 3, thousands to hundreds of thousands of times lower.

Plutonium-239’s DRLs are 732, versus an existing MCL and RAL of 15. Sm-151’s DRLs are

1,890,000 pCi in the new PAGs, versus an existing MCL of 1000 (and RAL of 6250), about a

factor of 2000-fold increase over Safe Drinking Water Levels. Nickel-63 has DRLs of 1,220,000

compared to an MCL of 50. And on and on, radionuclide by radionuclide, one sees massive

relaxation of standards

Figures 2-5 and Tables 2-5 show the vastly increased concentrations of radioactivity that

would be permitted under the new limits. For example, in Figure and Table 2, one sees that

limits for all radionuclides are increased by at least roughly two orders of magnitude, with many

increased by tens of thousands or even hundreds of thousands, with one increased by more than

seven million-fold. In Figure and Table 3, comparing the new DRL without decay to the current

MCL, the increases are all at least about two orders of magnitude, extending up to more than a

million-fold increase. In Figure and Table 4, the DRL with decay ranges from about two orders

of magnitude higher than the current RAL to about million times higher. And in Figure and

Table 5, the DRL without decay is up to a hundred thousand times higher than the RAL. The

radionuclide by radionuclide graphs that follow Table 5 show the astronomical increases in

radioactivity concentrations in drinking water proposed compared to current limits.

Discussion

The proposal to permit radioactive concentrations hundreds, thousands, tens and

hundreds of thousands, and even millions of times higher than current drinking water standards

is simply breathtaking. One cannot conceive what the EPA staffers who put forward these new

limits were thinking.

6

Providing replacement drinking water or requiring treatment of water supplies, when

regular water supplies are contaminated, is a relatively simple matter done all the time by EPA.

There simply is no reason to force people to drink highly contaminated water.

The EPA staffers who snuck these new limits into the PAG document may argue that it is

not appropriate to compare these levels to EPA’s Maximum Concentration Limits established

under the Safe Drinking Water Act, as they are supposedly based on more routine exposures, and

the DRLs are designed for nuclear incidents. However, the new PAGs define their scope as

applicable to any radioactivity release, which is defined as any release that could require

consideration of a protective action. They make clear they are for a wide range of releases, from

a full nuclear power plant accident to fires at fuel cycle facilities to releases from

radiopharmaceutical facilities to incidents involving transportation of radioactive materials.

Although there is a note in the PAGs saying they do not apply to site cleanups under

Superfund or the NRC decommissioning program, or other federal or state cleanup programs (p.

i), there is confusion as to how that assertion meshes with the statement of applicability of the

PAGs referred to above that says they apply to all radioactive releases for which a response may

be considered. Indeed, some within EPA have already pushed for abandoning EPA’s CERCLA

rules for Superfund cleanups and using instead the far more lenient PAGs. As Doug Guarino

reported in Inside EPA on 24 October 2008, “EPA in a new draft guidance on how the agency’s

regional Superfund officials should justify emergency response actions at toxic waste sites

suggests that for sites contaminated by radioactive substances, the officials should consult

guidelines for catastrophic nuclear emergencies [the new EPA PAGs] that are significantly less

stringent than traditional Superfund guidelines.“ There thus appears to be an effort to undermine

the entire structure of EPA’s radiation protection regime.

Additionally, EPA already has special standards for responding to radiological

emergencies – the Superfund RALs, which provide guidance for when immediate response in an

emergency situation is required. And the proposed DRLs are orders of magnitude less protective

than the existing RALs.

EPA staff may also argue that because the exposure in the intermediate phase of a nuclear

incident is expected to last only a year, they should be able to exposure people to a lifetime’s

worth of radiation in that one year. This is absurd. One isn’t going to be able to guarantee that

someone will have no additional radiation for the rest of their life, or hasn’t already had prior

exposures. And this is completely contradictory to longstanding EPA policy. EPA doesn’t

permit people to be exposed to higher than the MCL in any single year, irrespective of whether

prior years have been lower or one can somehow hope that future years will be as well.

Similarly, one doesn’t permit exposures over the RAL in any one year by claiming future years

may hopefully be brought under control. Furthermore, the PAGs make clear that the

intermediate phase may continue for years.

7

Conclusion

In short, the draft EPA Protective Action Guidelines would increase by hundreds,

thousands, and tens and hundreds of thousands of times or more the amount of radioactivity the

public may be forced to consume in drinking water. It is irresponsible, and senior EPA and

Administration officials should refuse to sign off on any such attempt.

TABLE 1

COMPARISON OF EPA’sPROPOSED

PROTECTIVE ACTION GUIDES[DERIVED RESPONSE LEVELS (DRLs)]

FOR RADIOACTIVITY IN DRINKINGWATER

vs.

EPA’s LONGSTANDING

MAXIMUM CONCENTRATION LIMITS(MCLs)

and

REMOVAL ACTION LEVELS(RALs)

TABLE 1: COMPARISON OF PROPOSED PROTECTIVE ACTION GUIDE'S DERIVED RESPONSE LEVELS (DRLs) vs. CURRENT

MAXIMUM CONCENTRATION LIMITS (MCLs) andREMOVAL ACTION LEVELS (RALs) for RADIOACTIVITY IN DRINKING WATER

Radionuclide DRL w/o Decay* DRL With Decay* MCL* RAL*

H-3 4,420,000 4,540,000 20,000 56,022

C-14 319,000 319,000 2,000 2,000

Na-22 58,000 66,100 400 400

P-32 77,100 1,370,000 30 315

S-35 239,000 731,000 500 5,960

Cl-36 199,000 199,000 700 891

Ca-45 260,000 513,000 10 1,116

Sc-46 125,000 397,000 100 513

V-48 93,400 1,460,000 90 417

Cr-51 4,790,000 43,700,000 6,000 18,405

Mn-54 257,000 374,000 300 1,345

Fe-55 557,000 631,000 2,000 2,924

Fe-59 103,000 591,000 200 389

Co-58 247,000 909,000 300 1,014

Co-60 53,900 57,600 100 192

Ni-63 1,220,000 1,220,000 50 4,902

Zn-65 46,900 75,400 300 300

Se-75 70,900 170,000 900 900

Rb-86 65,900 892,000 600 600

Sr-89 72,000 363,000 20 1,205

Sr-90 6,650 6,730 8 39

Y-90 68,800 6,530,000 60 196

Y-91 78,100 341,000 90 221

Zr-93 167,000 167,000 2,000 2,339

Zr-95 192,000 773,000 200 746

Nb-95 314,000 2,260,000 300 1,389

Mo-99 306,000 28,100,000 600 1,696

Tc-99 288,000 288,000 900 1,236

Ru-103 252,000 1,620,000 200 901

Ag-110m 66,500 106,000 90 315

Cd-109 92,600 120,000 600 612

In-114m 45,400 233,000 60 137

Sn-113 251,000 620,000 300 807

Sn-125 60,100 1,580,000 60 176

Sb-124 72,900 311,000 60 264

Te-127 1,100,000 712,000,000 900 3,435

Te-129 2,940,000 15,300,000,000 2,000 16,529

* units = picoCuries per Liter (pCi/L)

TABLE 1: COMPARISON OF PROPOSED PROTECTIVE ACTION GUIDE'S DERIVED RESPONSE LEVELS (DRLs) vs. CURRENT

MAXIMUM CONCENTRATION LIMITS (MCLs) andREMOVAL ACTION LEVELS (RALs) for RADIOACTIVITY IN DRINKING WATER

Radionuclide DRL w/o Decay* DRL With Decay* MCL* RAL*

Te-129m 62,300 468,000 90 221

Te-132 48,600 3,780,000 90 90

I-132 48,600 3,780,000 90 90

I-129 1,750 1,750 1 24

I-131 8,490 267,000 3 77

Cs-136 60,100 1,160,000 800 800

Cs-137 13,600 13,800 200 200

Ba-140 71,200 1,410,000 90 230

La-140 91,600 13,800,000 60 318

Ce-141 260,000 2,030,000 300 763

Ce-143 165,000 30,400,000 100 495

Ce-144 35,300 5,330,000 30 30

Nd-147 171,000 3,940,000 200 473

Pm-149 186,000 21,300,000 100 532

Sm-151 1,890,000 1,890,000 1,000 6,250

Eu-152 135,000 139,000 200 1,087

Eu-154 90,700 94,300 60 309

Eu-155 566,000 607,000 600 1,835

Gd-153 665,000 1,070,000 600 2,290

Tb-160 115,000 415,000 100 400

Tm-170 140,000 320,000 100 395

Hf-181 165,000 984,000 200 550

Ta-182 120,000 297,000 100 437

W-187 294,000 74,700,000 200 948

Ir-192 135,000 477,000 100 472

Au-198 180,000 16,900,000 100 559

Hg-203 96,900 529,000 60 60

Tl-204 156,000 170,000 300 553

Bi-207 146,000 147,000 200 604

Np-237 1,730 1,730 15 32

Pu-239 732 732 15 15

Am-241 907 908 15 19

Cm-243 1,240 1,260 15 21

* units = picoCuries per Liter (pCi/L)

TABLES 2-5FIGURES 2-5

SUMMARY COMPARISONS OF

EPA’S PROPOSED NEW PERMISSIBLE

CONCENTRATIONS OF RADIONUCLIDES

IN DRINKING WATER

[DERIVED RESPONSE LEVELS (DRLS)]

VS.

EPA’S LONGSTANDING RADIOACTIVITY

DRINKING WATER STANDARDS--MAXIMUM CONCENTRATION LIMITS

(MCLS)AND REMOVAL ACTION LEVELS (RALS)

NOTE: These comparisons focus on the beta particle- & photon-emitting radionuclides. Similardifferences exist with the new limits for alpha-emitting radionuclides. For the convenience ofthe reader, the Figures are numbered to correspond to the associated Table; there is no Figure 1.

Factor by which Allowable Radioactivity in Drinking Water is Proposed to IncreaseFIGURE 2: Proposed DRL (with Decay) vs. Current Maximum Concentration Level (MCL)

Page 1 of 3

227 160 165

45,700

1,460

284

51,300

3,970

16,200

7,280

1,250

316 296

3,030

576

24,400

251 189

1,490

18,200

841

109,000

1

10

100

1,000

10,000

100,000

1,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


Page 2 of 3

3,790

84

3,870 7,530

46,800

320

8,100

1,180

200

3,880 2,070

26,300

5,180

791,000

7,650,000

5,200

42,000 42,000

1,750

89,000

1,450

69

1

10

100

1,000

10,000

100,000

1,000,000

10,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


Page 3 of 3

15,700

230,000

6,770

304,000 178,000

19,700

213,000

1,890

695

1,570 1,010

1,780

4,150 3,200

4,920 2,970

374,000

4,770

800

8,820

567 735

1

10

100

1,000

10,000

100,000

1,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide

PROPOSED RELAXATION OF EPA DRINKING WATER STANDARDS

TABLE 2: Proposed Derived Response Level [DRL] (with Decay)vs. Current Maximum Concentration Level (MCL)

*Units = picoCuries per Liter (pCi/L)

Radionuclide PROPOSED DRL

w/ Decay*

CURRENT Maximum

Concentration Level (MCL)*

RATIO (Factor by which permissible concentration of

radioactivity in drinking water is proposed to increase)

H-3 4,540,000 20,000 227 C-14 319,000 2,000 160 Na-22 66,100 400 165 P-32 1,370,000 30 45,700 S-35 731,000 500 1,460 Cl-36 199,000 700 284 Ca-45 513,000 10 51,300 Sc-46 397,000 100 3,970 V-48 1,460,000 90 16,200 Cr-51 43,700,000 6,000 7,280 Mn-54 374,000 300 1,250 Fe-55 631,000 2,000 316 Fe-59 591,000 200 296 Co-58 909,000 300 3,030 Co-60 57,600 100 576 Ni-63 1,220,000 50 24,400 Zn-65 75,400 300 251 Se-75 170,000 900 189 Rb-86 892,000 600 1,490 Sr-89 363,000 20 18,200 Sr-90 6,730 8 841 Y-90 6,530,000 60 109,000 Y-91 341,000 90 3,790 Zr-93 167,000 2,000 84 Zr-95 773,000 200 3,870 Nb-95 2,260,000 300 7,530 Mo-99 28,100,000 600 46,800 Tc-99 288,000 900 320 Ru-103 1,620,000 200 8,100 Ag-110m 106,000 90 1,180 Cd-109 120,000 600 200 In-114m 233,000 60 3,880 Sn-113 620,000 300 2,070 Sn-125 1,580,000 60 26,300 Sb-124 311,000 60 5,180 Te-127 712,000,000 900 791,000


TABLE 2: Proposed Derived Response Level [DRL] (with Decay)vs. Current Maximum Concentration Level (MCL)



w/ Decay*

CURRENT Maximum


RATIO (Factor by which permissible concentration of

radioactivity in drinking water is proposed to increase)

Te-129 15,300,000,000 2,000 7,650,000 Te-129m 468,000 90 5,200 Te-132 3,780,000 90 42,000 I-132 3,780,000 90 42,000 I-129 1,750 1 1,750 I-131 267,000 3 89,000 Cs-136 1,160,000 800 1,450 Cs-137 13,800 200 69 Ba-140 1,410,000 90 15,700 La-140 13,800,000 60 230,000 Ce-141 2,030,000 300 6,770 Ce-143 30,400,000 100 304,000 Ce-144 5,330,000 30 178,000 Nd-147 3,940,000 200 19,700 Pm-149 21,300,000 100 213,000 Sm-151 1,890,000 1,000 1,890 Eu-152 139,000 200 695 Eu-154 94,300 60 1,570 Eu-155 607,000 600 1,010 Gd-153 1,070,000 600 1,780 Tb-160 415,000 100 4,150 Tm-170 320,000 100 3,200 Hf-181 984,000 200 4,920 Ta-182 297,000 100 2,970 W-187 74,700,000 200 374,000 Ir-192 477,000 100 4,770 Au-198 80,000 100 800 Hg-203 529,000 60 8,820 Tl-204 170,000 300 567 Bi-207 147,000 200 735

Factor by which Allowable Radioactivity in Drinking Water is Proposed to IncreaseFIGURE 3: Proposed DRL (without Decay) vs. Current Maximum Concentration Level (MCL)

Page 1 of 3

221 160 145

2,570

478

284

26,000

1,250 1,040 798 857

279

515 823

539

24,400

156

78 110

3,600

831 1,150

1

10

100

1,000

10,000

100,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of ra

dioa

ctiv

ity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


Page 2 of 3

868

84

960 1,050

510

320

1,260

739

154

757 837 1,000

1,220 1,220 1,470

692 540 540

1,750

2,830

75 68

1

10

100

1,000

10,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to

incr

ease

Radionuclide


Page 3 of 3

791 1,530

867 1,650

1,180 855

1,860 1,890

675

1,510 943 1,110 1,150 1,400

825 1,200 1,470 1,350

1,170,000

1,620

520 730

1

10

100

1,000

10,000

100,000

1,000,000

10,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


TABLE 3: Proposed Derived Response Level [DRL] (without Decay)vs. Current Maximum Concentration Level [MCL]



w/o Decay*

CURRENT Maximum


RATIO (Factor by which permissible concentration of radioactivity in

drinking water is proposed to increase)

H-3 4,420,000 20,000 221 C-14 319,000 2,000 160 Na-22 58,000 400 145 P-32 77,100 30 2,570 S-35 239,000 500 478 Cl-36 199,000 700 284 Ca-45 260,000 10 26,000 Sc-46 125,000 100 1,250 V-48 93,400 90 1,040 Cr-51 4,790,000 6,000 798 Mn-54 257,000 300 857 Fe-55 557,000 2,000 279 Fe-59 103,000 200 515 Co-58 247,000 300 823 Co-60 53,900 100 539 Ni-63 1,220,000 50 24,400 Zn-65 46,900 300 156 Se-75 70,900 900 78 Rb-86 65,900 600 110 Sr-89 72,000 20 3,600 Sr-90 6,650 8 831 Y-90 68,800 60 1,150 Y-91 78,100 90 868 Zr-93 167,000 2,000 84 Zr-95 192,000 200 960 Nb-95 314,000 300 1,050 Mo-99 306,000 600 510 Tc-99 288,000 900 320 Ru-103 252,000 200 1,260 Ag-110m 66,500 90 739 Cd-109 92,600 600 154 In-114m 45,400 60 757 Sn-113 251,000 300 837 Sn-125 60,100 60 1,000 Sb-124 72,900 60 1,220 Te-127 1,100,000 900 1,220


TABLE 3: Proposed Derived Response Level [DRL] (without Decay)vs. Current Maximum Concentration Level [MCL]



w/o Decay*

CURRENT Maximum


RATIO (Factor by which permissible concentration of radioactivity in

drinking water is proposed to increase)

Te-129 2,940,000 2,000 1,470 Te-129m 62,300 90 692 Te-132 48,600 90 540 I-132 48,600 90 540 I-129 1,750 1 1,750 I-131 8,490 3 2,830 Cs-136 60,100 800 75 Cs-137 13,600 200 68 Ba-140 71,200 90 791 La-140 91,600 60 1,530 Ce-141 260,000 300 867 Ce-143 165,000 100 1,650 Ce-144 35,300 30 1,180 Nd-147 171,000 200 855 Pm-149 186,000 100 1,860 Sm-151 1,890,000 1,000 1,890 Eu-152 135,000 200 675 Eu-154 90,700 60 1,510 Eu-155 566,000 600 943 Gd-153 665,000 600 1,110 Tb-160 115,000 100 1,150 Tm-170 140,000 100 1,400 Hf-181 165,000 200 825 Ta-182 120,000 100 1,200 W-187 294,000 200 1,470 Ir-192 135,000 100 1,350 Au-198 116,900,000 100 1,170,000 Hg-203 96,900 60 1,620 Tl-204 156,000 300 520 Bi-207 146,000 200 730

Factor by which Allowable Radioactivity in Drinking Water is Proposed to IncreaseFIGURE 4: Proposed DRL (with Decay) vs. Current Removal Action Level (RAL)

Page 1 of 3

81

160 165

4,350

123

223

460

774

3,500

2,370

278216

1,520

897

300249 251

189

1,490

301

171

33,300

1

10

100

1,000

10,000

100,000

H-3

C-14

Na-22

P-32

S-35

Cl-36

Ca-45

Sc-46

V-48

Cr-51

Mn-54

Fe-55

Fe-59

Co-58

Co-60

Ni-63

Zn-65

Se-75

Rb-86

Sr-89

Sr-90

Y-90

Radionuclide

Fac

tor

by

wh

ich

per

mis

sib

le c

on

cen

trat

ion

of

rad

ioac

tivi

ty in

dri

nki

ng

wat

er is

pro

po

sed

to

in

crea

se

Factor by which Allowable Radioactivity in Drinking Water is Proposed to IncreaseFIGURE 4: Proposed DRL (with Decay) vs. Current Removal Action Level

Page 2 of 3

1,540

71

1,040 1,630

16,600

233

1,800

337 196

1,700

769

8,980

1,180

207,000

926,000

2,120

42,000 42,000

74

3,480

1,450

69

1

10

100

1,000

10,000

100,000

1,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of ra

dioa

ctiv

ity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide

Factor by which Allowable Radioactivity in Drinking Water is Proposed to IncreaseFIGURE 4: Proposed DRL (with Decay) vs. Current Removal Action Level

Page 3 of 3

6,130

43,500

2,660

61,400

178,000

8,330

40,000

302

128

305 331 467

1,040 810

1,790

680

78,800

1,010

143

8,820

308 243

1

10

100

1,000

10,000

100,000

1,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to

incr

ease

Radionuclide


TABLE 4: Proposed Derived Response Level [DRL] (with Decay)vs. Current Removal Action Level [RAL]



w/ Decay* CURRENT Removal Action Level (RAL)*

RATIO (Factor by which permissible concentration of RADIOACTIVITY IN

DRINKING WATER IS PROPOSED TO INCREASE)

H-3 4,540,000 56,022 81 C-14 319,000 2,000 160 Na-22 66,100 400 165 P-32 1,370,000 315 4,350 S-35 731,000 5,960 123 Cl-36 199,000 891 223 Ca-45 513,000 1,116 460 Sc-46 397,000 513 774 V-48 1,460,000 417 3,500 Cr-51 43,700,000 18,405 2,370 Mn-54 374,000 1,345 278 Fe-55 631,000 2,924 216 Fe-59 591,000 389 1,520 Co-58 909,000 1,014 897 Co-60 57,600 192 300 Ni-63 1,220,000 4,902 249 Zn-65 75,400 300 251 Se-75 170,000 900 189 Rb-86 892,000 600 1,490 Sr-89 363,000 1,205 301 Sr-90 6,730 39 171 Y-90 6,530,000 196 33,300 Y-91 341,000 221 1,540 Zr-93 167,000 2,339 71 Zr-95 773,000 746 1,040 Nb-95 2,260,000 1,389 1,630 Mo-99 28,100,000 1,696 16,600 Tc-99 288,000 1,236 233 Ru-103 1,620,000 901 1,800 Ag-110m 106,000 315 337 Cd-109 120,000 612 196 In-114m 233,000 137 1,700 Sn-113 620,000 807 769 Sn-125 1,580,000 176 8,980 Sb-124 311,000 264 1,180 Te-127 712,000,000 3,435 207,000


TABLE 4: Proposed Derived Response Level [DRL] (with Decay)vs. Current Removal Action Level [RAL]



w/ Decay* CURRENT Removal Action Level (RAL)*

RATIO (Factor by which permissible concentration of RADIOACTIVITY IN

DRINKING WATER IS PROPOSED TO INCREASE)

Te-129 15,300,000,000 16,529 926,000 Te-129m 468,000 221 2,120 Te-132 3,780,000 90 42,000 I-132 3,780,000 90 42,000 I-129 1,750 24 74 I-131 267,000 77 3,480 Cs-136 1,160,000 800 1,450 Cs-137 13,800 200 69 Ba-140 1,410,000 230 6,130 La-140 13,800,000 318 43,500 Ce-141 2,030,000 763 2,660 Ce-143 30,400,000 495 61,400 Ce-144 5,330,000 30 178,000 Nd-147 3,940,000 473 8,330 Pm-149 21,300,000 532 40,000 Sm-151 1,890,000 6,250 302 Eu-152 139,000 1,087 128 Eu-154 94,300 309 305 Eu-155 607,000 1,835 331 Gd-153 1,070,000 2,290 467 Tb-160 415,000 400 1,040 Tm-170 320,000 395 810 Hf-181 984,000 550 1,790 Ta-182 297,000 437 680 W-187 74,700,000 948 78,800 Ir-192 477,000 472 1,010 Au-198 80,000 559 143 Hg-203 529,000 60 8,820 Tl-204 170,000 553 308 Bi-207 147,000 604 243

Factor by which Allowable Radioactibity in Drinking Water is Proposed to IncreaseFIGURE 5: Proposed DRL (without Decay) vs. Current Removal Action Level (RAL)

79

160 145

245

40

223 233 244 224 260

191 190

265 244 280

249

156

79

110

60

169

351

1

10

100

1,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


353

71

257 226

18

233 280

211

151

331 311 341 276

320

178

282

540 540

74

111

751

68

1

10

100

1,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of

radi

oact

ivity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


309 289 341 333

1,180

362 350 302

124

293 308 290 288 354 300 275 310 286

109,000

1,620

282 242

1

10

100

1,000

10,000

100,000

1,000,000

Fact

or b

y w

hich

per

mis

sibl

e co

ncen

trat

ion

of ra

dioa

ctiv

ity

in d

rinki

ng w

ater

is p

ropo

sed

to in

crea

se

Radionuclide


TABLE 5: Proposed Derived Response Level [DRL] (without Decay)vs. Current Removal Action Level [RAL]


Radionuclide PROPOSED DRL w/o Decay*

CURRENT Removal Action Level (RAL)*

RATIO (Factor by which permissible concentration of RADIOACTIVITY IN DRINKING WATER IS PROPOSED TO INCREASE)

H-3 4,420,000 56,022 79 C-14 319,000 2,000 160 Na-22 58,000 400 145 P-32 77,100 315 245 S-35 239,000 5,960 40 Cl-36 199,000 891 223 Ca-45 260,000 1,116 233 Sc-46 125,000 513 244 V-48 93,400 417 224 Cr-51 4,790,000 18,405 260 Mn-54 257,000 1,345 191 Fe-55 557,000 2,924 190 Fe-59 103,000 389 265 Co-58 247,000 1,014 244 Co-60 53,900 192 280 Ni-63 1,220,000 4,902 249 Zn-65 46,900 300 156 Se-75 70,900 900 79 Rb-86 65,900 600 110 Sr-89 72,000 1,205 60 Sr-90 6,650 39 169 Y-90 68,800 196 351 Y-91 78,100 221 353 Zr-93 167,000 2,339 71 Zr-95 192,000 746 257 Nb-95 314,000 1,389 226 Mo-99 306,000 16,946 18 Tc-99 288,000 1,236 233 Ru-103 252,000 901 280 Ag-110m 66,500 315 211 Cd-109 92,600 612 151 In-114m 45,400 137 331 Sn-113 251,000 807 311 Sn-125 60,100 176 341 Sb-124 72,900 264 276 Te-127 1,100,000 3,435 320


TABLE 5: Proposed Derived Response Level [DRL] (without Decay)vs. Current Removal Action Level [RAL]


Radionuclide PROPOSED DRL w/o Decay*

CURRENT Removal Action Level (RAL)*

RATIO (Factor by which permissible concentration of RADIOACTIVITY IN DRINKING WATER IS PROPOSED TO INCREASE)

Te-129 2,940,000 16,529 178 Te-129m 62,300 221 282 Te-132 48,600 90 540 I-132 48,600 90 540 I-129 1,750 24 74 I-131 8,490 77 111 Cs-136 60,100 800 751 Cs-137 13,600 200 68 Ba-140 71,200 230 309 La-140 91,600 318 289 Ce-141 260,000 763 341 Ce-143 165,000 495 333 Ce-144 35,300 30 1,180 Nd-147 171,000 473 362 Pm-149 186,000 532 350 Sm-151 1,890,000 6,250 302 Eu-152 135,000 1,087 124 Eu-154 90,700 309 293 Eu-155 566,000 1,835 308 Gd-153 665,000 2,290 290 Tb-160 115,000 400 288 Tm-170 140,000 395 354 Hf-181 165,000 550 300 Ta-182 120,000 437 275 W-187 294,000 948 310 Ir-192 135,000 472 286 Au-198 116,900,000 559 109,000 Hg-203 96,900 60 1,620 Tl-204 156,000 553 282 Bi-207 146,000 604 242

RADIONUCLIDE BY

RADIONUCLIDE

COMPARISON

PROPOSED NEW PERMISSIBLE

CONCENTRATIONS OF RADIONUCLIDES

IN DRINKING WATER (DRLS)

VS.

EPA’S LONGSTANDING DRINKING

WATER STANDARDS

(MCLS) AND (RALS)

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

4500000

5000000

H-3

DRL w/o Decay,

4,420,000 pCi/L

DRL With Decay,

4,540,000 pCi/L

MCL, 20,000 pCi/L

RAL, 56,022 pCi/L

DRL w/o Decay DRL With Decay MCL RAL

pCi/L

0

50000

100000

150000

200000

250000

300000

350000

C-14

DRL w/o Decay, 319,000 pCi/L

DRL With Decay, 319,000 pCi/L

MCL, 2,000 pCi/L

RAL, 2,000 pCi/L


pCi/L

0

10000

20000

30000

40000

50000

60000

70000

Na-22



MCL, 400

pCi/L

RAL, 400

pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

1400000

P-32


DRL With Decay,

1,370,000 pCi/L

MCL, 30

pCi/L

RAL, 315

pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

800000

S-35



MCL, 500

pCi/L

RAL, 5959.5 pCi/L


pCi/L

-

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

200,000

Cl-36



MCL, 700

pCi/L

RAL, 890.6 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

Ca-45



MCL, 10

pCi/L

RAL, 1,116.1 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

400000

Sc-46



MCL, 100

pCi/L

RAL, 512.8 pCi/L


pCi/L

-

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

V-48


DRL With Decay,

1,460,000 pCi/L

MCL, 90

pCi/L RAL, 416.7 pCi/L


pCi/L

0

5000000

10000000

15000000

20000000

25000000

30000000

35000000

40000000

45000000

Cr-51

DRL w/o Decay,

4,790,000 pCi/L

DRL With Decay,

43,700,000 pCi/L

MCL, 6000

pCi/L

RAL, 18,405 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

400000

Mn-54



MCL, 300

pCi/L

RAL, 1,345.3 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

Fe-55



MCL, 2000

pCi/L

RAL, 2924

pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

Fe-59



MCL, 200

pCi/L

RAL, 389.1 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

800000

900000

1000000

Co-58



MCL, 300

pCi/L

RAL, 1,013.5 pCi/L


pCi/L

0

10000

20000

30000

40000

50000

60000

Co-60



MCL, 100

pCi/L

RAL, 192.3 pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

1400000

Ni-63

DRL w/o Decay,

1,220,000 pCi/L

DRL With Decay,

1,220,000 pCi/L

MCL, 50

pCi/L

RAL, 4,902 pCi/L


pCi/L

0

10000

20000

30000

40000

50000

60000

70000

80000

Zn-65



MCL, 300

pCi/L

RAL, 300

pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

Se-75



MCL, 900

pCi/L

RAL, 900

pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

800000

900000

Rb-86



MCL, 600

pCi/L

RAL, 600

pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

400000

Sr-89



MCL, 20

pCi/L

RAL, 1,204.8 pCi/L


pCi/L

0

1000

2000

3000

4000

5000

6000

7000

Sr-90



MCL, 8

pCi/L

RAL, 39.4

pCi/L


pCi/L

0

1000000

2000000

3000000

4000000

5000000

6000000

7000000

Y-90


DRL With Decay,

6,530,000 pCi/L

MCL, 60

pCi/L

RAL, 196.1 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

Y-91



MCL, 90

pCi/L

RAL, 221.1 pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

Zr-93

DRL w/o Decay, 167,000

pCi/L

DRL With Decay, 167,000

pCi/L

MCL, 2,000 pCi/L

RAL, 2,339.2 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

800000

Zr-95



MCL, 200

pCi/L

RAL, 746.3 pCi/L


pCi/L

0

500000

1000000

1500000

2000000

2500000

Nb-95


DRL With Decay,

2,260,000 pCi/L

MCL, 300

pCi/L

RAL, 1,388.9 pCi/L


pCi/L

0

5000000

10000000

15000000

20000000

25000000

30000000

Mo-99


DRL With Decay,

28,100,000 pCi/L

MCL, 600

pCi/L

RAL, 1,695.9 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

Tc-99



MCL, 900

pCi/L

RAL, 1,236.3 pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

1800000

Ru-103


DRL With Decay,

1,620,000 pCi/L

MCL, 200

pCi/L

RAL, 900.9 pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

Ag-110m



MCL, 90

pCi/L

RAL, 314.7 pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

Cd-109



MCL, 600

pCi/L

RAL, 611.6 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

In-114m



MCL, 60

pCi/L

RAL, 137.3 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

Sn-113



pCi/L

MCL, 300

pCi/L

RAL, 806.5 pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

Sn-125


DRL With Decay,

1,580,000 pCi/L

MCL, 60

pCi/L

RAL, 176

pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

Sb-124



MCL, 60

pCi/L

RAL, 264.3 pCi/L


pCi/L

0

100000000

200000000

300000000

400000000

500000000

600000000

700000000

800000000

Te-127

DRL w/o Decay,

1,100,000 pCi/L

DRL With Decay,

712,000,000 pCi/L

MCL, 900

pCi/L

RAL, 3,435.1 pCi/L


pCi/L

0

2E+09

4E+09

6E+09

8E+09

1E+10

1.2E+10

1.4E+10

1.6E+10

Te-129

DRL w/o Decay,

2,940,000 pCi/L

DRL With Decay,

15,300,000,000 pCi/L

MCL, 2,000 pCi/L

RAL, 16,528.9

pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

400000

450000

500000

Te-129m



pCi/L

MCL, 90

pCi/L

RAL, 221.1 pCi/L


pCi/L

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

Te-132


DRL With Decay,

3,780,000 pCi/g

MCL, 90

pCi/L RAL,

90 pCi/L


pCi/L

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

I-132


DRL With Decay,

3,780,000 pCi/L

MCL, 90

pCi/L

RAL, 90

pCi/L


pCi/L

0

200

400

600

800

1000

1200

1400

1600

1800

I-129



MCL, 1

pCi/L

RAL, 23.7 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

I-131



pCi/L MCL,

3 pCi/L

RAL, 76.7 pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

Cs-136


DRL With Decay,

1,160,000 pCi/L

MCL, 800

pCi/L

RAL, 800

pCi/L


pCi/L

0

2000

4000

6000

8000

10000

12000

14000

Cs-137



MCL, 200

pCi/L RAL, 200

pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

Ba-140


DRL With Decay,

1,410,000 pCi/L

MCL, 90

pCi/L

RAL, 230.2 pCi/L


pCi/L

0

2000000

4000000

6000000

8000000

10000000

12000000

14000000

La-140


DRL With Decay,

13,800,000 pCi/L

MCL, 60

pCi/L

RAL, 317.5 pCi/L


pCi/L

0

500000

1000000

1500000

2000000

2500000

Ce-141


pCi/L

DRL With Decay,

2,030,000 pCi/L

MCL, 300

pCi/L

RAL, 763.4 pCi/L


pCi/L

0

5000000

10000000

15000000

20000000

25000000

30000000

35000000

Ce-143


pCi/L

DRL With Decay,

30,400,000 pCi/L

MCL, 100

pCi/L

RAL, 495

pCi/L


pCi/L

0

1000000

2000000

3000000

4000000

5000000

6000000

Ce-144


DRL With Decay,

5,330,000 pCi/L

MCL, 30

pCi/L

RAL, 30

pCi/L


pCi/L

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

Nd-147


pCi/L

DRL With Decay,

3,940,000 pCi/L

MCL, 200

pCi/L

RAL, 472.8 pCi/L


pCi/L

0

5000000

10000000

15000000

20000000

25000000

Pm-149


pCi/L

DRL With Decay,

21,300,000 pCi/L

MCL, 100

pCi/L

RAL, 531.9 pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

1800000

2000000

Sm-151

DRL w/o Decay,

1,890,000 pCi/L

DRL With Decay,

1,890,000 pCi/L

MCL, 1000 pCi/L

RAL, 6250 pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

140000

Eu-152


pCi/L


pCi/L

MCL, 200

pCi/L

RAL, 1,087 pCi/L


pCi/L

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000

Eu-154



MCL, 60

pCi/L

RAL, 309.3 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

Eu-155


pCi/L


pCi/L

MCL, 600

pCi/L

RAL, 1834.9 pCi/L


pCi/L

0

200000

400000

600000

800000

1000000

1200000

Gd-153


pCi/L

DRL With Decay,

1,070,000 pCi/L

MCL, 600

pCi/L

RAL, 2,290.1 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

400000

450000

Tb-160



pCi/L

MCL, 100

pCi/L

RAL, 400

pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

Tm-170


pCi/L


pCi/L

MCL, 100

pCi/L

RAL, 395.3 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

700000

800000

900000

1000000

Hf-181


pCi/L


pCi/L

MCL, 200

pCi/L

RAL, 549.5 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

Ta-182


pCi/L


pCi/L

MCL, 100

pCi/L

RAL, 436.7 pCi/L


pCi/L

0

10000000

20000000

30000000

40000000

50000000

60000000

70000000

80000000

W-187


pCi/L

DRL With Decay,

74,700,000 pCi/L

MCL, 200

pCi/L

RAL, 947.9 pCi/L


pCi/L

0

50000

100000

150000

200000

250000

300000

350000

400000

450000

500000

Ir-192


pCi/L


pCi/L

MCL, 100

pCi/L

RAL, 471.7 pCi/L


pCi/L

0

20000000

40000000

60000000

80000000

100000000

120000000

Au-198

DRL w/o Decay,

116,900,000 pCi/L


MCL, 100

pCi/L

RAL, 558.7 pCi/L


pCi/L

0

100000

200000

300000

400000

500000

600000

Hg-203



pCi/L

MCL, 60

pCi/L

RAL, 60

pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

Tl-204


pCi/L


pCi/L

MCL, 300

pCi/L

RAL, 552.5 pCi/L


pCi/L

0

20000

40000

60000

80000

100000

120000

140000

160000

Bi-207


pCi/L


pCi/L

MCL, 200

pCi/L

RAL, 604.2 pCi/L


pCi/L

TABLE 6

DERIVATION OF CURRENT

EPAREMOVAL ACTION LEVELS

(RALS)FOR RADIOACTIVITY IN

DRINKING WATER

NOTE: Existing EPA standards for when alternative drinking water supplies are to be providedin emergency situations are the Removal Action Levels (RALs). They are derived by calculatingthe concentration of a particular radionuclide that will produce a 10 –4 (1 in 10,000) cancer riskand then comparing that concentration with the Maximum Concentration Limit (MCL) specifiedby EPA under the Safe Drinking Water Act. Whichever is greater is used as the RAL. See EPApolicy for when to provide drinking water during emergencies and the method for deriving RALsin Final Guidance on Numeric Removal Action Levels for Contaminated Drinking Water Sites,25 October 1993, from Deborah Dietrich, Director, Emergency Response Division, EPA. EPA’scurrent risk figures for converting MCLs to RALs are found in Radionuclides Notice of DataAvailability, prepared by Targeting and Analysis Branch, Standards and Risk ManagementDivision, USEPA Office of Ground Water and Drinking Water, in collaboration with USEPAOffice of Indoor Air & Radiation and the U.S. Geological Survey, March 2000. The followingtable for beta particle and photon-emitting radionuclides calculates the 10 –4 concentration usingthe above EPA-specified methodology (the risk figures are from Table III-3 of the RadionuclidesNotice of Data Availability), compares it to the MCL, and identifies the RAL that derivestherefrom. [The 10 –4 concentrations for determining RALs for alpha-emitting radionuclides arereported directly in Table III-4 of that document.]

TABLE 6: CALCULATION OF REMOVAL ACTION LEVELS (RALs)and comparisons with Proposed Derived Response Levels (DRLs) and Existing

Maximum Concentration Levels (MCLs)

* Units - picoCuries per Liter (pCi/L)

Radionuclide DRL w/o Decay* DRL With Decay*

Maximum Containment Level (MCL)*

Cancer Risk for (MCL) 10-4 Cancer Risk

Removal Action Level (RAL)*

H-3 4,420,000 4,540,000 20,000 3.57E-05 56,022 56,022 C-14 319,000 319,000 2,000 1.09E-04 1,835 2,000 Na-22 58,000 66,100 400 1.36E-04 294 400 P-32 77,100 1,370,000 30 9.53E-06 315 315 S-35 239,000 731,000 500 8.39E-06 5,959 5,960 Cl-36 199,000 199,000 700 7.86E-05 891 891 Ca-45 260,000 513,000 10 8.96E-07 1,116 1,116 Sc-46 125,000 397,000 100 1.95E-05 513 513 V-48 93,400 1,460,000 90 2.16E-05 417 417 Cr-51 4,790,000 43,700,000 6,000 3.26E-05 18,405 18,405 Mn-54 257,000 374,000 300 2.23E-05 1,345 1,345 Fe-55 557,000 631,000 2,000 6.84E-05 2,924 2,924 Fe-59 103,000 591,000 200 5.14E-05 389 389 Co-58 247,000 909,000 300 2.96E-05 1,014 1,014 Co-60 53,900 57,600 100 5.20E-05 192 192 Ni-63 1,220,000 1,220,000 50 1.02E-06 4,902 4,902 Zn-65 46,900 75,400 300 1.23E-04 244 300 Se-75 70,900 170,000 900 2.65E-04 340 900 Rb-86 65,900 892,000 600 2.06E-04 291 600 Sr-89 72,000 363,000 20 1.66E-06 1,205 1,205 Sr-90 6,650 6,730 8 2.03E-05 39 39 Y-90 68,800 6,530,000 60 3.06E-05 196 196 Y-91 78,100 341,000 90 4.07E-05 221 221 Zr-93 167,000 167,000 2,000 8.55E-05 2,339 2,339 Zr-95 192,000 773,000 200 2.68E-05 746 746 Nb-95 314,000 2,260,000 300 2.16E-05 1,389 1,389 Mo-99 306,000 28,100,000 600 3.54E-05 1,695 1,695 Tc-99 288,000 288,000 900 7.28E-05 1,236 1,236 Ru-103 252,000 1,620,000 200 2.22E-05 901 901 Ag-110m 66,500 106,000 90 2.86E-05 315 315 Cd-109 92,600 120,000 600 9.81E-05 612 612 In-114m 45,400 233,000 60 4.37E-05 137 137

TABLE 6: CALCULATION OF REMOVAL ACTION LEVELS (RALs)and comparisons with Proposed Derived Response Levels (DRLs) and Existing

Maximum Concentration Levels (MCLs)

* Units - picoCuries per Liter (pCi/L)

Sn-113 251,000 620,000 300 3.72E-05 806 807 Sn-125 60,100 1,580,000 60 3.41E-05 176 176 Sb-124 72,900 311,000 60 2.27E-05 264 264 Te-127 1,100,000 712,000,000 900 2.62E-05 3,435 3,435 Te-129 2,940,000 15,300,000,000 2,000 1.21E-05 16,529 16,529 Te-129m 62,300 468,000 90 4.07E-05 221 221 Te-132 48,600 3,780,000 90 2.13E-04 42 90 I-132 48,600 3,780,000 90 1.98E-04 45 90 I-129 1,750 1,750 1 4.22E-06 24 24 I-131 8,490 267,000 3 3.91E-06 77 77 Cs-136 60,100 1,160,000 800 2.42E-04 331 800 Cs-137 13,600 13,800 200 1.27E-04 157 200 Ba-140 71,200 1,410,000 90 3.91E-05 230 230 La-140 91,600 13,800,000 60 1.89E-05 317 318 Ce-141 260,000 2,030,000 300 3.93E-05 763 763 Ce-143 165,000 30,400,000 100 2.02E-05 495 495 Ce-144 35,300 5,330,000 30 2.60E-04 12 30 Nd-147 171,000 3,940,000 200 4.23E-05 473 473 Pm-149 186,000 21,300,000 100 1.88E-05 532 532 Sm-151 1,890,000 1,890,000 1,000 1.60E-05 6,250 6,250 Eu-152 135,000 139,000 200 1.84E-05 1,087 1,087 Eu-154 90,700 94,300 60 1.94E-05 309 309 Eu-155 566,000 607,000 600 3.27E-05 1,835 1,835 Gd-153 665,000 1,070,000 600 2.62E-05 2,290 2,290 Tb-160 115,000 415,000 100 2.50E-05 400 400 Tm-170 140,000 320,000 100 2.53E-05 395 395 Hf-181 165,000 984,000 200 3.64E-05 549 550 Ta-182 120,000 297,000 100 2.29E-05 437 437 W-187 294,000 74,700,000 200 2.11E-05 948 948 Ir-192 135,000 477,000 100 2.12E-05 472 472 Au-198 116,900,000 80,000 100 1.79E-05 559 559 Hg-203 96,900 529,000 60 5.70E-04 11 60 Tl-204 156,000 170,000 300 5.43E-05 552 553 Bi-207 146,000 147,000 200 3.31E-05 604 604

Errata

The Au-198 DRLs are correct in Table 1 but were incorrectly transcribed in the subsequenttables and figures. The correct DRL without decay is 180,000 pCi/L and with decay 16,900,000pCu/L.

proposed relaxation of epa drinking water standards …

Documents